Differential valve



C, F. PECKHAM DIFFERENTIAL VALVE July 5, 1932.

c: F. PECKHAM 1,866,319

n DIFFERENTIAL VALVE Filed April S, 1926 2 Sheets-Sheet 2 latented July 5, 1932 UNIT-Enf STATES! `oiretitnus F. PECKHAM, oF PROVIDENCE, RHODE ISLAND; ISABELLER.' DECKHAM, Ex-

ECUTRIX OF'SABfCI-ARL-ES F. PECKHAIVI,

DFFERENTIAL VALVE o K l Appiicationmea Aprii s,

This invention relates to improvements in differential valves, particularly dry-pipe valves, for'use ywith the sprinkler systems ofL automatic fire-extinguishingapparatus, The. il

improvements are directedv especially to that type of valve shown in my prior. United States Letters PatentY No. 1,618,478, dated January 4,1927. 'p Oneobject of the present'improvement is 'o provide a' valve of the type specified having a minimum number of parts of simpli-y fied construction. v V,

Another object of the improvementisto provide a'valve requiring very little machining or finishing on its interior, the valve seats and valve clapper or closure'being `con`v structed as separate elements: which may be machined and finished body or casing.

Another object of the'iinprovement is to provide a valve of the type yspecified having its closure or clapper constructed as la loosel or separate part withoutpivoted or hinged`- joints or other fitted connections. 'o

Another object of the' improvementisto provide a valve of compact form, minimumv weight, and one whichvis economical tov manl 'A with a water-seat and an air-seat which'are.

formed on andy constituted in a removable describes a preferredembodiment of the iii`- vention as illustrated by the accompanying drawings. In the drawings: o

Fig. 1 is a vertical sectional view ofthe im,- proved valve taken on its main axis, and showing the valve-closure full lines as seated, and in dotted lines as raised off from itsseat;and Y Fig. 2 is a sectional plan view of the valve taken on line 2-,2 of Fig. 1 and showing the valve-closure displaced laterally from its seat,

Referring toFig. 1 ofthe drawings, in the present embodiment of the invention the improved valve comprises a'body `or lcasi1'ig'2 provided with a flanged/inlet 3' and an op,J posite flanged outlet et which, as here shown,

are substantially concentr icwithv thevertical axis passingthrough'the center of the valve.

For the purpose of this description the'inletvr apart from the Vvalve I 1926'. serial No. 100,570.Y

the supply-chamber of the valve, while its en# PATENT LoFi-m which is surrounded by a flange 8 disposedY in a vertical plane. A cover-plate 10 is fittedY to the flange Sand held in place thereagainst by 'means of suitable bolts 11. Preferably, the cover l0 is'suspended from a hinge, not hereinv illustrated, to adapt it tov swing away from the side of the valve when the bolts 11 are removed. Y o

`rlhe cover 10 takes the formof a vert-icalv plate 12 having a semi-circular pocket-like eX tension 14 pro] ecting froniitsside and inclinedv downwardly therefrom, see` Fig. 2 vand braced'from the main plate by ribs 13. The Y,

pocket or extension 14 forms the receptacle or chamber for the gravity-operated clapper or closure 15 which isuadapt'ed tol slide thereinto when released from its seatin the manner vas hereinafter more fully explained.

Y The valve clapp'er or closure 15 cooperates erably constructed as a. bronze casting which may be machined to ther oontour'illustrated.

' As sliownin Fig. 1, the' bottom of the annu-- f lus or valve-ring'ly is faced olf at 17 to adapt itto lit against thel finished face 18 on thefinf.

' clined floor or bottom wall 6 of the valve bodyl 2. Above this face'17 is an annular pocket or channel 19 for receiving nuts 20 screwed on-V to the ends of studs 21 which project Vup through the annulus as shown in Fig. Y1; the

arrangementof the studs and nuts Circuni'- ferentially of the annulus being illustrated in'Fig.' 2. The central ,opening 22 ofthel` annulus 16 is provided at `the top with an inwardly projecting flange or lipr 23the`in-,-

'ner edge of which forms areduced' water.-

throat 24, while 'itsupper face 25jformsth`e c -waterseat for the closure or'clapper 15. f'

ido

On the outer periphery or rim of the annulus 16 is an overhanging flange 27 provided with a reentrant groove or channel 28. The channel 28 is filled with a ring of block-tin 29, the upper face of which is beveled off to form an air-seat 30 which is inclined at a slight angle to the plane of the Water-seat 25.

Within the annular channel 19' at one side of the valve-throat is a drip-valve 35 which is. adapted to be tripped.'automatically from an arm 36, seeFig.V 2,'carrying an adjustable screw 37 at its end which is engaged by the bottom of the clapper or closure-1'5. The. drip-valve 35 is of usual arrangement and therefore needs no further description-here Y ofthe` outletv 4 of the valve-casing for connectinga test gauge 5, a small inlet 39`is provided in the delivery-chamber 5 for admit'- tingwaterfto primethe valve; and a drain n valve'40leads from the inlet or supply-chainpoint, "being normally closed by suitable cock, not herein shown.

The clapper or valve-closure 15 is vpreferably constructed in the form of a` relatively flat' diski'which may bea. brassor bronze casting. The under side ofthe disk or clapper 15 is faced oil' at 45.A toadaptI it todit close against the water-seat 25' on the valve-ring or annulus 16. lOn the top of'lthedisl the. metalis cut away in a cylindriuz'al'.depressi'on- 46to save unnecessary' weight, and'eXtendingv across the depression and'screwed tothe flat. rim.49 at 50 is a strip 48 whichprovidesa Outwardly bel yondtherim 49 of the disk 151 is an annular handle for the clapper.

i i depression. or channelV 51 which, further. re-

duces the weight ofthe clapperwhile.they

annular tapered rim-49 provides a rib or ,re-

enforcement to stiflen its central portion.

which rests against the water-seat 25 on the annulus 16.

Referring to Fig. 2 the` cl1annel' 51isy bridged by suitable radial ribs 54.which further:y brace and stienf the clapper. The.

4outermostrim ofthe disk 15'is ,beveled'off at 53,' and fittedthereto is a rubber ring or. washer`55 of substantially frusto-coni'califormrin cross-section.V The rubber annulus 55functionsas an air-valve,v its outer rim. being yadapted to flex. and to fit snugly againstthe inclined air-seat 30 of the tin annulus 29. The air-ring 55 is clamped against the beveled rim 53 of the clapper 15 by means of an outer metal ring or annulus 56 secured to the clapper by suitable rivets or screws 57. A clearance is provided between the bottom faicerof the outerfrini of the clapper: 1:5 and the upper' face ofthe valve annulus 16, but formedV on this face of the clapper is an annula-rL rimor shoulder. GOada-pted to: lit within the outeredgeof the channel 19 in the annulus 16. This flange or rim 60 engaging with therrecessed rim of the annulus 16 provides a detent or locating means for the elapper tol hold? it inconcentric relation with respect to the valve-seats against which it rests; this construction replacing the pinandi-groove detent means for theA clapper as illustrated in my prior Patent N o. 1,613,478 above referred= to.

Referring to Fig.v2, a relatively iatshel'f or web 61.. extends downwardly from theriml ofthe valve-annulus 16and'i`s provided with a horizontally extending bead or ledge 62V which serves as arrest for the valve-clapper 15 when the lat-ter slides off from its seat on the valve-ring 16.

Projecting inwardly from the vertical plate 12,1 of thel cover V1()V is, a. rounded rib or lug 63 which providesan abutment or stop against which the rim ofthe clapper 15 is adapted tQ strike when` the latter is raised oiffrom i'tsseat. Fig. l2, a pair of curved ribs or ways project fromtheinterior walls of the valve casing 2 at the top of-theid'elivery-chamber 5. These guides or, waysv 64 are adapted to engagethe circular rimiof'the clapper to guide it in its movement as it lifts orfrom the` water-seat. As showninFig. 1the curve. ofthe ways 64 is plotted more. or` less to the shape of a cam'whereby as one edge of the clapper is held by the abutment 63 the lifting of itsopposite side asitrides along the ways will cause the clapper to slidev downwardly to direct it into the pocket 14 in the cover 10.

Inthis manner the clapperis prevented from Thev method'4 of operation. of the improved I valveislas follows: Underznormal conditions the clapper'15 .isseated onrthe valve-annulus 16, withfits annular-trim or shoulder 60engagingthe edgeorrim ofthe. recess-19 in the Referring particularly to.

vlar edge of the ring 16.

seat-ring; In this position 4theY bottom Aof the clapper rests-against the Water-seat to close. the. supply-throat of thevalve; while the flexible annulus rests against the airferred to, the present valve operates on the differential principle, that'is, with alesser pressure acting upon the greater area on the delivery side of the clapper maintaining the clapper closed against the greater. pressure acting upon the lesser area within its waterseat on the supply side. As before noted, the present improved valve is designed for use particularly with dry-pipe systems in whichk there is no water in the sprinkler pipes when the valve is'closed. It is the usualpractice, however, to prime the valve with a small quantity of water' which is admitted to the delivery-chainber 5 of the casing 2 through a suitable by-pass or funnel connected to the opening 39. The water acts to make a better seal for the air-seat and prevents the annulus 55 from becoming hard 515 is relieved or reduced to normal atmospheric pressure, whereupon the water-head on the under .side of the disk or clapper 15 will raise the latter off from its seat sufficiently t0 releaseits rim 60 from the annurdinarily the clapper will be raised off from its seat only a slight distance, for as the water commences to flow across the edge of the water-.seat 25 the pressure heads in the supply-chamber and delivery-chamber undergo a change in value. In other words, there is a loss of pressure head under the clapper 15 so that it will not be forced violently upward or shot away from its .seat-ring.

As the clapper 15 is raised ofi' from its seat the action of gravity will cause it to move downwardly to the right, as viewed in Fig. 1, with its bottom sliding across the ledge 62. The force of the stream flowing through the inlet of the valve will also have a tendency to carry the clapper in thisdirection. whereby it will .slide down into the pocket 14 in the cover 10 to entirely remove it from the inlet-port 0r orifice. n

If there is a tendency for the clapper to be lifted with any force, as in the case of an abnormal relief of the air pressure, its outer rim will strike against the abutment or lug 63 on the cover 10 whereby to prevent the "clapper from up-tilting or turning over in the direction ofthe outlet4 of the valve.

At the same time, the opposite rimof the clapper 15 is engaged with or restsagainst the curved ribs or ways 64 extending across the upper. n

part of the interior of the valve casing 2. rlliis edge of the clapper will therefore slide alonfT these ribs or uidewa 's which bein in tlieform ofja cam, will act to slidethe valve laterally across its seat and downward` ly into. the pocket 14. In this way the valveclapper is prevented from blocking or obstructingthe flow through the outlet 4 of the valve; its release from the valve-seat and its lateralr displacement thereacross being rende-red more prompt and positive. As the clapper 15 Vdrops down into the pocket 14 its edgestrikes against the buffer element 65, which, being ofv softmetal, preventschipping or @renting-the rim ofthe clapper.-

- To re-seat the valve it is only necessary to remove the cover 10 on the main ycasing 2,. whereupon the clapper may be lifted byits 1 handle 48`and setback on its seat on the ring. or annulus 16. ln seating the clapper 15 its flange 60 is engaged with the annular .out-

er edgeA of the-channel 19` in the ring-16 and the clapper is then rotated back and forth to. make sure that it is properly seated. After the elapperis re-seated the cover 10 is closed again* and the valve primed an-d set for/operation as above explained...

ItI will be observed that the present improve-ment provides a valve of the utmost simplicity, having a minimum number of part-s adapted for economic-al manufacture.: vThe valve-.seats are embodied in the ring or annulus 16 which is made separate from the main valve body or casing 2. VThis provides that the valve-se-ats may be machined and finished apart from the casing itself, the machining operations being performed on a part of relatively small dimensions in a lathe or any other suitablemachine tool. Likewise, the valve clapper 15 is` manufactured and machined as a separate part. This eliminates practically. all machining within the valve-casing except thev facing o' of the seat 18 against The valve-body or casing may be made as a simple casting and is of compact form and minimum weight. Likewise, the seat-ring lao and clapper are .small in dimension andlight v in weight sothat the who-le valve is further rendered more economical to manufacture. Y

It will be understood that while I have. herein illustrated a preferred embodiment of my improve-d valve various modifications v maybe made in the construction and arrangement of its partswithoutdeparting fromthespirit or Vscope of the invention.

Therefore, without limitingy myself in this respect, I claim: f

l. In a differentialv valve', the combination of. a casing having ,an inlet-port surrounded. by an annular rim, and an unconnected float-- ing valve-closure adapted to seat across the lport and provided with a shouldered annulus engaging the surrounding rim thereof to maintain the closure in register with the port7 said valve provided with an air-seat having a greater area opposed to the pressure in thevalvo-casing than its area opposed tov the pressure through the inlet-port.

2. In a differential valve, the combination of a casing. having an inlet-port opening thereinto, a sea-ring surrounding the'port' and provided with a recessed rim and an outer annular air-seat, a freely iioatingclapper adapted to seat across the portv and provided with a shouldered annulus adapted to engage the rim of the seat-ring to maintain the clapper concentric therewith, and a flexible annulusv on the clapper adapted to cooperate with the air-seat on the seat-ring.4

3. In a differential valve7 the combination' of a casing having an inletport opening` thereinto,a seat-ringr` surrounding said opening and provided withA a central' waterseat, said seat-ring also formed with an annular ldepression and an outer air-.seat7 a clapper adapted to rest across the watereseat'and'provided with an annular shoulder engaging the rim of the depression in the seat`ring,

and a iexible annulus carried on the rim ofr 'l an annulary shoulder engaging the edge of the annular channel in the seat-ring, and a iiexible annulus on the clapper adapted to rest against the annular air-seat on the ring 5. In a differential valve the combination of a casing having an inlet-port with an in clined water-seat,A a free clapper adapted to seat across said port with a greater area ofits surface opposed to the pressurein the casing than its area opposed to the pressure Vthrough the port,v means Jfor normallyretaining the clapper in concentric relation:

with respect to the port7 said clapper adaptedl to be lifted off from its seat to release its re`` taining means to cause it to slide'v laterally-r 6. Inai diierentialn valve, the. combination of a casing having an inlet-port, a seat-ring.

surrounding the inlet-port and provided with` an inclined water-seat7 a clapper adapted to rest across the water-seat with a4 greater area of its surface opposed to the 'pressurein the casing thanY its area opposed CERTIFCATE 0F CGRREG'EN.

Patent No. 1,866,319. July 5, 1932.

CHARLES F. PECKHAM, eseaseii whose Execurix is SABELLE R. PEQKHAM.

i is hereby certified that emu appeas iai me printed specification o he above numbered patent feqraiing @affection as fcviiaws: Page 4, lim 16, caim 2, for "sea-ring" read seat-ring; ami that the Said ittrs Patent should be read with this correcion therein that ie sama sexism io he record of the case in the Patent Office.

Signed and sealed this Zith day of ctoer, A. B. 1932.

M. J. Moore, (Seal) Aciiag ommissioner of Patens. 

